• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.04a
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• pp.93-99
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• 2011

Proton-NMR spectroscopic method was applied to kinetics study of concentrated sulfuric acid hydrolysis reaction. Xylan was used as model compounds. Without neutralization steps in proton-NMR methods, this analysis method is valid for analysis of xylose, furfural and formic acid in acid hydrolyzates.

• Korean Journal of Pharmacognosy
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• v.33 no.2 s.129
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• pp.96-99
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• 2002

20-Hydroxyecdysone was isolated from Melandrii Herba and identified by the spectroscopic methods. In order to evaluate the quality of it, quantitative determination of 20-hydroxyecdysone in Melandrii Herba using HPLC method has been conducted. Content of 20-hydroxyecdysone in Melandrii Herba showed average 0.0138% in 42 samples collected throughout the regions of Korea.

• Journal of the Korean Wood Science and Technology
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• v.41 no.4
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• pp.287-292
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• 2013

Reaction of glucose and xylose to secondary hydrolysis of concentrated acid hydrolysis was quantitatively analyzed by $^1H$-NMR spectroscopic method. Anomeric hydrogen, furan and formic acid peaks were selected for quantitative analysis. The glucose was converted to the formic acid and the levulinic acid via the 5-hydroxymethylfurfural (HMF) but the xylose was converted to the fufural, which further degraded to the formic acid. The conversion to furans was slower for the glucose than the xylose. But the 5-HMF formed from the glucose was unstable in acidic aqueous medium, resulted in fast conversion to the levulinic acid and the formic acid. The furfural was relatively stable than 5-HMF at acidic aqueous medium.

• Near Infrared Analysis
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• v.2 no.1
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• pp.43-53
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• 2001

A non-invasive spectroscopic method is presented for the measurement of pulmonary edema. Both early diagnosis and quantitative edema estimates were investigated. The spectroscopic determination of pulmonary edema involved the acquisition of diffuse reflectance spectra in the near-infrared (NIR) region with change in water concentration - water is the main constituent of edema fluid. Pulmonary edema was induced into the excised perfused lungs of seven animals by elevating the hydrostatic pressure. Estimates of edema were ascertained from a partial least squares regression of the measured spectral response. Actual edema was determined from the change (increase) in total lung weight. Estimates in relative lung weight increases due to in vitro edema were made with the near infrared spectra. The results revealed that fluid accumulation produced spectral changes in the O-H and C-H absorptions as well as scattering changes in the spectra. Histology of the lung was used to verify the presence or absence of interstitial and alveolar edema. Results demonstrated that near infrared spectroscopy might provide a new tool for clinical assessment of pulmonary edema.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.1
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• pp.72.3-72.3
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• 2015

We present the mid-infrared (MIR) luminosity function (LF) of local (z < 0.3) star forming (SF) galaxies based on the AKARI's NEP-Wide Survey data. We utilized a combination of the NEP-Wide point source catalogue containing a large number (114,000) of infrared (IR) sources distributed over the wide (5.4 sq. deg) field and spectroscopic redshift (z) data for 1790 selected targets obtained by optical follow-up surveys with MMT/Hectospec and WIYN/Hydra. The AKARI's continuous $2{\sim}24{\mu}m$ wavelength coverage and the spectroscopic redshifts for sample galaxies enable us to derive accurate spectral energy distributions (SEDs) in the mid-infrared. We carried out SED-fit analysis and employed 1/Vmax method to derive the mid-IR (e.g., $8{\mu}m$, $12{\mu}m$, and $15{\mu}m$ rest-frame) luminosity functions. Our results for local galaxies from the NEP region generally consistent with various previous works for other fields over wide luminosity ranges. The comparison with the results of the NEP-Deep data implies the luminosity evolution from higher redshifts towards the present epoch. We attempted to fit our derived LFs to the double power-laws and present the resulting power indices. We also examined the correlation between mid-IR luminosity and total IR luminosity.

• Proceedings of the KOSOMBE Conference
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• v.1997 no.05
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• pp.303-308
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• 1997

In this paper, we analyzed the spectroscopic properties of strip to analyzer urine qualitatively & quantitatively and make urine analyzer system stable by spectroscopy, and research the property of preamplifier unit. The analysis of spectroscopic properties of 10 pads in the strip is used for determine the wave length of light source of optic detector unit and used for basic materials which are necessary that we develop the algorithm analyzing the density grade of pad accurately. We make preamplifier unit by using the current to frequency method to measure the distribution of pad color. We implemented urine analyzer system. This system's hardware is composed of measuring unit for detect of distribution density of strip pad, main processing unit, communication unit, interface device, thermal printer, and indicator. The software consists of the program which manage the argument of test, proportion initial value of urine analyzer and calibrate analyzed result.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.73-73
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• 2010

Various organic- and bio-conjugated nanoparticles have been studied extensively for biological applications in medical diagnoses and drug delivery systems. Gold nanoparticles (AuNP) and poly(ethylene glycol) (PEG) are known biocompatible materials to be used in vivo and are becoming increasingly important in biomedical applications. In this work, we investigated the stability of PEG-conjugated AuNPs, dialysis and centrifuge effects after synthesis or pegylation of AuNPs as a function of elapsed time by using ToF-SIMS imaging technique along with dynamic light scattering (DLS), UV-visible absorption spectroscopic and statistical analyses. Roughly 15-nm-sized AuNPs were synthesized in a citrate-conjugated form, and then converted into the thiol-terminated PEG (O-[2-(3-Mercaptopropionylamino)ethyl]-O'-methylpolyethyleneglycol, M.W.=5 kDa) form. Based on our data, we will show that ToF-SIMS imaging analysis along with DLS, UV-visible absorption and statistical analyses would be a useful method to evaluate stability of PEG-conjugated AuNPs in various environmental conditions.

• Near Infrared Analysis
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• v.1 no.1
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• pp.23-26
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• 2000

The objectives of this study were to examine the ability to predict soluble solid and firmness in intact apple based on the visible/near-infrared spectroscopic technique. Two cultivars of apples, Delicious and Gala, were handled, tested and analyzed. Reflectance spectra, Magness-Taylor (MT) Firmness, and soluble solids in apples were measured sequentially. Maximum and minimum diameters, height, and weight of apples were recorded before the MT firmness tests. Apple samples were divided in to a calibration set and a validation set. The method of partial least squares (PLS) analysis was used. a unique set of PLS loading vectors (factors) was development for soluble solid and firmness. The PLS model showed good relationship between predicted and measured soluble solids in intact apples in the wavelength range of 860∼1078 nm. However, the PLS analysis was not good enough to predict the apple firmness.

• Korean Journal of Pharmacognosy
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• v.32 no.4 s.127
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• pp.322-326
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• 2001

For the quality control of Leonuri Herba, alkaloid compound, leonurine, was isolated from the MeOH extract of Leonurus sibiricus L. (Labiatae) and identified by the spectroscopic analysis. A quantitative analysis of leonurine using HPLC method showed that the average contents were $0.124{\pm}0.065%$ in 34 samples collected throughout the regions of Korea.

• Korean Journal of Pharmacognosy
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• v.32 no.2 s.125
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• pp.157-162
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• 2001

For the quality control of Cassiae Semen, anthraquinone compound, aurantio-obtusin, was isolated from the MeOH extract of Cassiae Semen (Leguminosae) and identified by the spectroscopic analysis. A quantitative analysis of aurantio-obtusin using HPLC method showed that the average contents of aurantio-obtusin were $0.03{\pm}0.01%$ in 50 samples collected throughout the various regions of Korea.